xref: /linux/drivers/gpu/drm/msm/msm_gem_vma.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2016 Red Hat
4  * Author: Rob Clark <robdclark@gmail.com>
5  */
6 
7 #include "msm_drv.h"
8 #include "msm_fence.h"
9 #include "msm_gem.h"
10 #include "msm_mmu.h"
11 
12 static void
13 msm_gem_address_space_destroy(struct kref *kref)
14 {
15 	struct msm_gem_address_space *aspace = container_of(kref,
16 			struct msm_gem_address_space, kref);
17 
18 	drm_mm_takedown(&aspace->mm);
19 	if (aspace->mmu)
20 		aspace->mmu->funcs->destroy(aspace->mmu);
21 	put_pid(aspace->pid);
22 	kfree(aspace);
23 }
24 
25 
26 void msm_gem_address_space_put(struct msm_gem_address_space *aspace)
27 {
28 	if (aspace)
29 		kref_put(&aspace->kref, msm_gem_address_space_destroy);
30 }
31 
32 struct msm_gem_address_space *
33 msm_gem_address_space_get(struct msm_gem_address_space *aspace)
34 {
35 	if (!IS_ERR_OR_NULL(aspace))
36 		kref_get(&aspace->kref);
37 
38 	return aspace;
39 }
40 
41 /* Actually unmap memory for the vma */
42 void msm_gem_vma_purge(struct msm_gem_vma *vma)
43 {
44 	struct msm_gem_address_space *aspace = vma->aspace;
45 	unsigned size = vma->node.size;
46 
47 	/* Don't do anything if the memory isn't mapped */
48 	if (!vma->mapped)
49 		return;
50 
51 	aspace->mmu->funcs->unmap(aspace->mmu, vma->iova, size);
52 
53 	vma->mapped = false;
54 }
55 
56 /* Map and pin vma: */
57 int
58 msm_gem_vma_map(struct msm_gem_vma *vma, int prot,
59 		struct sg_table *sgt, int size)
60 {
61 	struct msm_gem_address_space *aspace = vma->aspace;
62 	int ret;
63 
64 	if (GEM_WARN_ON(!vma->iova))
65 		return -EINVAL;
66 
67 	if (vma->mapped)
68 		return 0;
69 
70 	vma->mapped = true;
71 
72 	if (!aspace)
73 		return 0;
74 
75 	/*
76 	 * NOTE: iommu/io-pgtable can allocate pages, so we cannot hold
77 	 * a lock across map/unmap which is also used in the job_run()
78 	 * path, as this can cause deadlock in job_run() vs shrinker/
79 	 * reclaim.
80 	 *
81 	 * Revisit this if we can come up with a scheme to pre-alloc pages
82 	 * for the pgtable in map/unmap ops.
83 	 */
84 	ret = aspace->mmu->funcs->map(aspace->mmu, vma->iova, sgt, size, prot);
85 
86 	if (ret) {
87 		vma->mapped = false;
88 	}
89 
90 	return ret;
91 }
92 
93 /* Close an iova.  Warn if it is still in use */
94 void msm_gem_vma_close(struct msm_gem_vma *vma)
95 {
96 	struct msm_gem_address_space *aspace = vma->aspace;
97 
98 	GEM_WARN_ON(vma->mapped);
99 
100 	spin_lock(&aspace->lock);
101 	if (vma->iova)
102 		drm_mm_remove_node(&vma->node);
103 	spin_unlock(&aspace->lock);
104 
105 	vma->iova = 0;
106 
107 	msm_gem_address_space_put(aspace);
108 }
109 
110 struct msm_gem_vma *msm_gem_vma_new(struct msm_gem_address_space *aspace)
111 {
112 	struct msm_gem_vma *vma;
113 
114 	vma = kzalloc(sizeof(*vma), GFP_KERNEL);
115 	if (!vma)
116 		return NULL;
117 
118 	vma->aspace = aspace;
119 
120 	return vma;
121 }
122 
123 /* Initialize a new vma and allocate an iova for it */
124 int msm_gem_vma_init(struct msm_gem_vma *vma, int size,
125 		u64 range_start, u64 range_end)
126 {
127 	struct msm_gem_address_space *aspace = vma->aspace;
128 	int ret;
129 
130 	if (GEM_WARN_ON(!aspace))
131 		return -EINVAL;
132 
133 	if (GEM_WARN_ON(vma->iova))
134 		return -EBUSY;
135 
136 	spin_lock(&aspace->lock);
137 	ret = drm_mm_insert_node_in_range(&aspace->mm, &vma->node,
138 					  size, PAGE_SIZE, 0,
139 					  range_start, range_end, 0);
140 	spin_unlock(&aspace->lock);
141 
142 	if (ret)
143 		return ret;
144 
145 	vma->iova = vma->node.start;
146 	vma->mapped = false;
147 
148 	kref_get(&aspace->kref);
149 
150 	return 0;
151 }
152 
153 struct msm_gem_address_space *
154 msm_gem_address_space_create(struct msm_mmu *mmu, const char *name,
155 		u64 va_start, u64 size)
156 {
157 	struct msm_gem_address_space *aspace;
158 
159 	if (IS_ERR(mmu))
160 		return ERR_CAST(mmu);
161 
162 	aspace = kzalloc(sizeof(*aspace), GFP_KERNEL);
163 	if (!aspace)
164 		return ERR_PTR(-ENOMEM);
165 
166 	spin_lock_init(&aspace->lock);
167 	aspace->name = name;
168 	aspace->mmu = mmu;
169 	aspace->va_start = va_start;
170 	aspace->va_size  = size;
171 
172 	drm_mm_init(&aspace->mm, va_start, size);
173 
174 	kref_init(&aspace->kref);
175 
176 	return aspace;
177 }
178